Intelligence is how smart your Noul is. Intelligence effects how quick a Noul is at picking up tricks, training, and increasing stats. It also effects how it will react in a tough situation. A very important stat.
Agility is how easily a Noul can change direction when running, speed means little without agility.
Speed is how fast a Noul can run.
Stamina is how long your Noul can continue at a certain pace. It usually runs hand in hand with speed and/or strength.
Strength is, obviously, how strong a Noul is. How much weight it can carry or pull, and how easily it might defeat another Noul with pure bodily strength.
Conformation is how a Noul carries it self. Although not a particularily useful stat, it is essential when showing.
Defense is how much 'brutal assault' a Noul can withstand. Again, not that important unless the Noul is going to be a fighter or battling the harsh weathers of sled racing.
Obediance is much like intelligence. It determines how well you're Noul is going to do in training and the like, but also whether or not it will obey your commands at crucial moments in events.

Stats can be anywhere between 1 and 100, at these levels (natural stats are only between 1-50, you'll have to train to get to the good stuff!):
Extremely Poor: 1-10
Poor: 11-25
Moderate: 26-50
Good: 51-80
Excellent: 81-99
Perfect: 100